Affect, emotions and moods

Affect: a broad range of feelings that people experience. Affect can be experienced in the form of emotions or moods.

Emotions are caused by specific event, very brief in duration (seconds or minutes), specific and numerous in nature (many specific emotions such as anger, fear, sadness, happiness, disgust, surprise).
Usually accompanied by distinct facial expressions.
Action oriented in nature.

Moods: Cause is often general and unclear. Last longer than emotions (hours or days). More general (two main dimensions - positive affect and negative affect - that are comprised of multiple specific emotions)
Generally not indicated by distinct expressions. Cognitive in nature.